I recently purchased a used 2011 Ford Edge (91K miles) and noticed the outer driver's side CV joint making noise during sharp turns. Pulled the left axle and disassembled the outer CV joint. In the attached photo you can see that every surface where the balls contact there is pitting. The boot was not damaged so all the grease was there and no dirt entered the joint. Not sure why this occurred, it seems unusual for all 8 surfaces to have pitting like this but this was the case and what was causing the noise during sharp turns. I replaced the axle with an OEM Motorcraft part from Rockauto.
The used Edge was maintained well with all service done at the dealership. Overall it's is very good condition but I did miss the CV joint noise when I checked it out before purchase. I also missed a small power steering high pressure hose leak so had to also replace this hose.
All is well now and I'm impressed with the Ford, it's quiet, powerful and handles reasonably well. It's the limited model so some nice features and the interior is also nice and comfortable. Really like it so far.